Pyrazolone derivative.



UN STATES PATENT -OFFICE. FRIEDRICH sroi z, or Hoc sr-QNJHEMAIN GERMANY; Assion'on TO rannwnm vonm. mnrsrna LUCIUS a naflmne, or tSoHS'r-oN -TH E-MAIN, GERMANY, a con- PORATION F i PYRAZOLONE nnmvarrvn.

1,053,240. No Drawing.

, "*Speciflcation of Letters Patent. Application filed Kay 14,1912. Serial m5. 097,324.

Patented Feb. 18, 1913.

To all whom it may concern: 7 I

Be it known that I, FRIEDRICH Sronz, Ph.

D., chemist, a citizen of the Empire of Germany, residing at Hiichst-on-the-Main, Germany, have invented certain'new and useful Improvements in Pyrazolone' Derivatives, of which the following is a specification.

I have found that by causin iodin to act upon 1- (p-bromphenyl)-2-3- imethyl-5- yrazolone,'a new compound: the l-(pararomphenyl) 2.3-diinethyl-4-iodo 5 pyrazclone is obtained. This compound is of great therapeutical value and can be usedas a substitute for potassium iodid. It acts both as a sedative and as an antipyretic, and does not produce the undesirable secondary efi'ects by which the administration of potassium iodid is attended.

The following example illustrates my in- I vention, the parts being by weight: 254 parts of owdered 'iodm are introduced While stirring into a solution of 267 parts of 1 (para bromphenyl) =2 3 dimethyl- 5-pyrazolone (Ber-z'chte vol. 33, page 2609) in 800 parts of benzene, and the mixture is heated for two hours-to 5060 C. After having added a solution of 75 parts of anhydrous sodium carbonate in 450 parts of water, the whole is digested for 46 hours in the refiux-appara tuaion the water bath.

.The. benzene solution is separated from the aqueous solution, and after washing, first" I I with a dilute solution of bisulfite and afterward with sodium carbonate for removing the excess of iodin, zene distilled oil". The remaining product of the reaction is recrystallized in alcohol and then forms colorless crystals, melting at 163 C., scarcely soluble in water, dilficultly soluble in diluted hydrochloric acid, readily soluble in hot alcohol and benzene.

Havin now described my invention, what I c aim, is: As a new product, the 1- (para-bromphenyl)'- 2-3-dimethyl-4-iodo- 5 pyra-z olone, having the constitution CH3-NNCQHBI om-o-ci- 0 being colorless crystals melting at 163'C., scarcely. soluble in water, difiicultly soluble in diluted hydrochloric acid, readily soluble in hot alcohol and benzene.

In testimony whereof, I aflix my signature in presence of two witnesses FRIEDRICH STOLZ- Witnesses:

JEAN GRUND, CARL GRUND.

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